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Protecting-group-free synthesis of 3-tert-prenylated oxindoles: contiguous all-carbon quaternary centers via tertiary neopentyl substitution.

ABSTRACT: Ruthenium-catalyzed tert-prenylation of isatin 1 occurs efficiently in the absence of N-protecting groups under the conditions of C-C bond-forming transfer hydrogenation employing 1,1-dimethylallene as the prenyl donor. The prenylated adduct, 3-hydroxy-3-tert-prenyl-oxindole 2, is converted to the tertiary neopentyl chloride 3, which participates in nucleophilic substitution by way of an aza-o-xylylene intermediate to furnish adducts 4a-4i. Through tertiary neopentyl substitution, two contiguous all-carbon quaternary centers are established.

SUBMITTER: Grant CD

PROVIDER: S-EPMC2760743 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Protecting-group-free synthesis of 3-tert-prenylated oxindoles: contiguous all-carbon quaternary centers via tertiary neopentyl substitution.

Grant Christopher D CD Krische Michael J MJ

Organic letters 20091001 20

Ruthenium-catalyzed tert-prenylation of isatin 1 occurs efficiently in the absence of N-protecting groups under the conditions of C-C bond-forming transfer hydrogenation employing 1,1-dimethylallene as the prenyl donor. The prenylated adduct, 3-hydroxy-3-tert-prenyl-oxindole 2, is converted to the tertiary neopentyl chloride 3, which participates in nucleophilic substitution by way of an aza-o-xylylene intermediate to furnish adducts 4a-4i. Through tertiary neopentyl substitution, two contiguous ...[more]

PMID: 19764718

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